Drilling buckets



DeC- 12,1967 P. DE BOSREDON DRILLINKG BUCKETS Filed June 29, 1.965

United States Patent O 3,357,506 DRILLING BUCKETS Pierre de Bosredon, 14 Rue Duron, Bergerac, Dordogne, France Filed .lune 29, 1965, Ser. No. 467,963 Claims priority, application France, July 28, 1964, 983,301, Patent 1,410,326 4 Claims. (Cl. 175-99) ABSTRACT OF THE DISCLOSURE A drill bucket is suspended by means of a fastening system adapted to hold the bucket against vertical motion, before actuating the bucket shells, by bearing against the walls of the shaft being drilled.

Grab ybucket devices are already known for drilling prisrnaticor circular-sectioned wells or shafts.

In certain known devices of this character the bucket is caused to penetrate or dig the ground by causing the excavator boom to exert a pressure on the bucket. However, this method is applicable only to specific cases wherein the well or shaft to be made is of relatively reduced depth. `If a substantial depth is required the bucket must be suspended from a rope and the penetration is obtained in some cases by allowing the bucket to fall freely from a certain height, this method requiring a heavy and sturdy bucket. Moreover, the heterogeneous structure of the ground may tend to deflect the line of fall of the bucket from a straight line, thus compromising the balanced conditions of operation of the two bucket shells.

Another known device consists in causing the bucket to penetrate like a drill into the ground with the assistance of a to-and-fro motion obtained from a complicated hydraulic or mechanical assembly, and reclosing the shells after a predetermined degree of sinking has been attained.

It is the object of this invention to provide a drill bucket which is both particularly simple in construction and perfectly reliable in operation.

To this end, this drill bucket is suspended by means of a fastening system adapted to hold the bucket against vertical motion, before actuating the shells, by bearing against the walls of the shaft.

The features and advantages characterizing this invention will appear more completely from the following description given by way of example with reference to the diagrammatic drawing attached hereto, wherein:

FIGURE l shows in axial section the bucket lowered to the bottom of the well or shaft being dug.

FIGURE 2 shows the same bucket after the locking in position of the fastening system.

FIGURES 3 and 4 are plan views showing the different forms of embodiment of the fastening system in the position shown in FIGURE 2.

The bucket 1 of a conventional type is actuated by means of a hydraulic cylinder 2 the expansion and contraction of which cause the closing and opening of the pair of shells 3 of the bucket by means of arms 4. In FIGURE 2 the shells are shown in their open position in thick lines (at 3) and in their closed position in dash lines (at 3a). These shells may be shaped for drilling a cylindrical or prismatic-sectioned well.

This bucket 1 is suspended from a lrope |11 by means of a fastening system comprising essentially at least two guide plates 5 of a shape consistent with the crosssectional contour of the projected shaft or Well (assumed to be circular in this example). These guide plates 5 are pivotally connected for example on the one hand to the body 6 of a singleor double-acting cylinder 6 by 3,357,506 Patented Dec. 12, 1967 JCC means of links 7 and on the other hand to the piston -rod 8 of this cylinder by means of another set of links 9. These guide plates 5 are suspended from the lower end of a suspension and operating rope 11 by means of slings 13 attached Ito the pivot points of the outer ends of the upper links 9. In case the cylinder 6, 8 is of the singleacting type, traction springs 10 will contract the cylinder assembly and hold the fastening system in the retracted position shown in FIGURE l when no fluid under pressure is supplied to this cylinder.

The bucket thus suspended from the fastening system operates as follows:

The bucket positioned as shown in FIGURE l is lowered into the then completed shaft portion until the shells 3 contact the bottom thereof. Then the cylinder 6, 8 is expanded and the guide plates 5 are pressed against the walls 12 of the shaft. Expanding the cylinder 2 will then move the shells 3 to the position 3a of FIGURE 2, thus filling the bucket with material to be rejected. The cylinder 6, 8 is subsequently contracted to move the guide plates 5 away from the walls 12 of the well, and the bucket 1 may be raised by pulling the rope 11 and its contents is finally discha-rged eX-ternally of the shaft.

The hydraulic control device for actuating the cylinders 2 and 6, 8 may be constructed with a view to produce mutually synchronized movements, or servoaction movements or independent movements, at will.

In drillings in firm grounds not requiring the casing of shafts, the guide plates 5 engage the walls directly. If the ground is soft or such as to require the use of casing elements to be lowered as the drilling progresses, the guide plates 5 bear on the previously fitted casing portion.

Of course, many modifications may be brought to the constructional details described hereinabove with reference to the drawing without departing from the spirit and scope of the invention as set forth in the appended claims.

What I claim is:

I1. A drilling apparatus comprising a bucket consisting of a hydraulic-operated cylinder having a bearing element and a working element movable in relation -to said bearing element, shells pivoted on said bearing element, links pivoted on said shells and said Working element of said cylinder, a fastening system supporting said bearing element of the bucket cylinder, means for suspending said fastening system, said fastening system comprising a hydraulic control cylinder having a lower end connected to the bearing element of the bucket hydraulic cylinder and an upper end, surface guide members corresponding in shape to sectors of the wall of the shaft being drilled, links having outer ends pivotally connected to said surface guide members `and inner ends pivotally connected to the lower and upper ends, respectively, of said hydraulic control cylinder, the operation of said control cylinder in the direction to reduce its length freeing said guide members from the shaft being drilled, the operation of said control cylinder in the direction to increase its length causing said guide members to be locked together with the complete fastening system on said sectors of the shaft wall.

2. A drilling apparatus as set forth in claim 1, wherein said cylinder for controlling said fastening system is a double-acting cylinder.

3. A drilling apparatus as set forth in claim 1, wherein said fastening system comprises spring means attached to both ends of said control cylinder and constantly urging same to its retracted position in which said control cylinder releases the surface guide members from the 0 wall of the shaft being drilled, said control cylinder 3 4 4. A drilling apparatus as set forth in claim 1, whe-re- 2,501,594 3/ 1950 Billings 37-187 in said means for suspending the fastening system Con- 3,113,629 12/196'3 Allard 175-238 sist of suspension slings attached to the pivot points in 3,194,329 7/1965 Wal-1ers n 175 315 said surface guide members of the aforesaid links pivoted on the other hand to the upper end of said cylinder con- 5 FOREIGN PATENTS trolling sald fastening system. 870,383 3/1953 Germany- References Cited CHARLES E oCoNv LL P UNITED STATES PATENTS l E nmaly Examzner.

2,223,645 12/194()I Solomon 175--94 10 NILE C- BYERS, Examiner- 2,499,508 `3/1950 Karhu 175-285 X 

1. A DRILLING APPARATUS COMPRISING A BUCKET CONSISTING OF A HYDRAULIC-OPERATED CYLINDER HAVING A BEARING ELEMENT AND A WORKING ELEMENT MOVABLE IN RELATION TO SAID BEARING ELEMENT, SHELLS PIVOTED ON SAID BEARING ELEMENT, LINKS PIVOTED ON SAID SHELLS AND SAID WORKING ELEMENT OF SAID CYLINDER, A FASTENING SYSTEM SUPPORTING SAID BEARING ELEMENT OF THE BUCKET CYLINDER, MEANS FOR SUSPENDING SAID FASTENING SYSTEM, SAID FASTENING SYSTEM COMPRISING A HYDRAULIC CONTROL CYLINDER HAVING A LOWER END CONNECTED TO THE BEARING ELEMENT OF THE BUCKET HYDRAULIC CYLINDER AND AN UPPER END, SURFACE GUIDE MEMBERS CORRESPONDING IN SHAPE TO SECTORS OF THE WALL OF THE SHAFT BEING DRILLED, LINKS HAVING OUTER ENDS PIVOTALLY CONNECTED TO SAID SURFACE GUIDE MEMBERS AND INNER ENDS PIVOTALLY CONNECTED TO THE LOWER AND UPPER ENDS, RESPECTIVELY, OF SAID HYDRAULIC CONTROL CYLINDER, THE OPERATION OF SAID CONTROL CYLINDER IN THE DIRECTION TO REDUCE ITS LENGTH FREEING SAID GUIDE MEMBERS FROM THE SHAFT BEING DRILLED, THE OPERATION OF SAID CONTROL CYLINDER IN THE DIRECTION TO INCREASE ITS LENGTH CAUSING SAID GUIDE MEMBERS TO BE LOCKED TOGETHER WITH THE COMPLETE FASTENING SYSTEM ON SAID SECTORS OF THE SHAFT WALL. 